The long-term goal of this project is to develop and commercialize a neurostimulation product comprised of a small battery-powered implanted stimulator and electrodes placed in the triceps muscle on or near the radial nerve motor points to control reaching via electrical stimulation. Tendon transfers have long been the primary intervention for improving upper extremity function in individuals with spinal cord injury involving the upper extremities. In particular, Posterior Deltoid to Triceps transfers have provided tremendous functional benefit to quadriplegic patients. However, this non-reversible surgical process requires extensive surgical intervention, prolonged post-operative immobilization and extended rehabilitation. The goal of this Phase I project is to determine the feasibility of our approach to stimulate triceps and achieve a functional muscle contraction in persons with tetraplegia. At the conclusion of this Phase I project, we will have determined the feasibility of providing elbow extension through electrical stimulation of the radial nerve innervation to the triceps using a small implanted microstimulator. Also, we intend to compare the amount of time and effort it takes to restore a functional elbow extension through a neuroprosthesis compared to that of performing a standard posterior deltoid to triceps transfer. [unreadable] [unreadable]